Borehole nuclear magnetic resonance(NMR)is a powerful technology to characterize the petrophysical properties of underground reservoirs in the petroleum industry.The rising complexity of oil and gas exploration and de...Borehole nuclear magnetic resonance(NMR)is a powerful technology to characterize the petrophysical properties of underground reservoirs in the petroleum industry.The rising complexity of oil and gas exploration and development objectives,as well as the novel application contexts of underground reservoirs,have led to increasingly demanding requirements on borehole NMR technology including instrument design and related processing methods.This mini review summarizes the advances and applications of borehole NMR instruments along with some future possibilities.It may be helpful for researchers and engineers in the petroleum industry to understand the development status and future trends of borehole NMR technology.展开更多
It is of great significance to study how temperature affects the restricted diffusion in pores for an accurate evaluation of reservoir physical properties by using nuclear magnetic resonance(NMR)diffusion-transverse r...It is of great significance to study how temperature affects the restricted diffusion in pores for an accurate evaluation of reservoir physical properties by using nuclear magnetic resonance(NMR)diffusion-transverse relaxation(D-T2)spectrum under reservoir temperature conditions.In this paper,we simulate the restricted diffusion and twodimensional(2D)NMR D-T2 spectra of water molecules at different temperatures using random-walk method.The one-dimensional(1D)restricted diffusion simulation results show that the diffusion coefficient in the pore at room temperature decays with the diffusion time and eventually reaches a plateau.Under the condition of long-time diffusion,the ratio of restricted diffusion coefficient to bulk diffusion coefficient at different temperatures tends to be the same constant.With the increase in temperature,the simulated D-T2 spectra also gradually move upward.The simulated D-T2 spectra at all temperatures are consistent with the Pade interpolation equation.In addition,the results calculated by Pade interpolation equation demonstrate that the degree of temperature influence on the D-T2 spectrum of rock is quantitatively related to the pore radius,porosity and cementation index.展开更多
The measurement of nuclear magnetic resonance(NMR)porosity is affected by temperature.Without considering the impact of NMR logging tools,this phenomenon is mainly caused by variations in magnetization intensity of th...The measurement of nuclear magnetic resonance(NMR)porosity is affected by temperature.Without considering the impact of NMR logging tools,this phenomenon is mainly caused by variations in magnetization intensity of the measured system due to temperature fluctuations and difference between the temperature of the porous medium and calibration sample.In this study,the effect of temperature was explained based on the thermodynamic theory,and the rules of NMR porosity responses to temperature changes were identified through core physics experiments.In addition,a method for correcting the influence of temperature on NMR porosity measurement was proposed,and the possible factors that may affect its application were also discussed.展开更多
Early insulin therapy is capable to achieve glycemic control and restoreβ-cell function in newly diagnosed type 2 diabetes(T2D),but its effect on cardiovascular outcomes in these patients remains unclear.In this nati...Early insulin therapy is capable to achieve glycemic control and restoreβ-cell function in newly diagnosed type 2 diabetes(T2D),but its effect on cardiovascular outcomes in these patients remains unclear.In this nationwide real-world study,we analyzed electronic health record data from 19 medical centers across China between 1 January 2000,and 26 May 2022.We included 5424 eligible patients(mean age 56 years,2176 women/3248 men)who were diagnosed T2D within six months and did not have prior cardiovascular disease.Multivariable Cox regression models were used to estimate the associations of early insulin therapy(defined as the first-line therapy for at least two weeks in newly diagnosed T2D patients)with the incidence of major cardiovascular events including coronary heart disease(CHD),stroke,and hospitalization for heart failure(HF).During 17,158 persons years of observation,we documented 834 incident CHD cases,719 stroke cases,and 230 hospitalized cases for HF.Newly diagnosed T2D patients who received early insulin therapy,compared with those who did not receive such treatment,had 31%lower risk of incident stroke,and 28%lower risk of hospitalization for HF.No significant difference in the risk of CHD was observed.We found similar results when repeating the aforesaid analysis in a propensity-score matched population of 4578 patients and with inverse probability of treatment weighting models.These findings suggest that early insulin therapy in newly diagnosed T2D may have cardiovascular benefits by reducing the risk of incident stroke and hospitalization for HF.展开更多
Coronavirus disease 2019(COVID-19)is regarded as an endothelial disease(endothelialitis)with its patho-mechanism being incompletely understood.Emerging evidence has demonstrated that endothelial dysfunction precipitat...Coronavirus disease 2019(COVID-19)is regarded as an endothelial disease(endothelialitis)with its patho-mechanism being incompletely understood.Emerging evidence has demonstrated that endothelial dysfunction precipitates COVID-19 and its accompanying multi-organ injuries.Thus,pharmacotherapies targeting endothelial dysfunction have potential to ameliorate COVID-19 and its cardiovascular complications.The objective of the present study is to evaluate whether kruppel-like factor 2(KLF2),a master regulator of vascular homeostasis,represents a therapeutic target for C0VID-19-induced endothelial dysfunction.Here,we demonstrate that the expression of KLF2 was reduced and monocyte adhesion was increased in endothelial cells treated with COVID-19 patient serum due to elevated levels of pro-adhesive molecules,ICAM1 and VCAM1.IL-1β and TNF-α;two cytokines elevated in cytokine release syndrome in COVID-19 patients,decreased KLF2 gene expression.Pharmacologic(atorvastatin and tannic acid)and genetic(adenoviral overexpression)approaches to augment KLF2 levels attenuated COVID-19-serum-induced increase in endothelial inflammation and monocyte adhesion.Next-generation RNA-sequencing data showed that atorvastatin treatment leads to a cardiovascular protective transcriptome associated with improved endothelial function(vasodilation,antiinflammation,antioxidant status,anti-thrombosis/-coagulation,anti-fibrosis,and reduced angiogenesis).Finally,knockdown of KLF2 partially reversed the ameliorative effect of atorvastatin on COVID-19-serum-induced endothelial inflammation and monocyte adhesion.Collectively,the present study implicates loss of KLF2 as an important molecular event in the development of COVID-19-induced vascular disease and suggests that efforts to augment KLF2 levels may be therapeutically beneficial.展开更多
Dear Editor,In January 2020,a widespread outbreak of coronavirus disease 2019(COVID-19)occurred after the beginning of the largest annual migration in China,which is known as the Spring Festival migration.Starting in ...Dear Editor,In January 2020,a widespread outbreak of coronavirus disease 2019(COVID-19)occurred after the beginning of the largest annual migration in China,which is known as the Spring Festival migration.Starting in January 20,2020,the Chinese government took a series of unprecedented measures to contain the spread of COVID-19.Because of the role of Wuhan as a central transportation hub.展开更多
Background: Data on the glycemic profile of pregnant women with gestational diabetes mellitus (GDM) during the perinatal period are sparse. This study described the intrapartum and early postpartum glucose profiles am...Background: Data on the glycemic profile of pregnant women with gestational diabetes mellitus (GDM) during the perinatal period are sparse. This study described the intrapartum and early postpartum glucose profiles among pregnant women with GDM, and analyzed factors potentially affecting glycemic parameters during the period.Methods: This was a prospective observational study conducted from March 2020 to November 2021. Pregnant women with GDM receiving lifestyle interventions alone during pregnancy and matched women with non-diabetic pregnancies (NDPs) were enrolled from among patients admitted to the obstetrics department for childbirth. Glucose monitoring was performed via a flash glucose monitoring (FGM) system on admission, and glucose readings during labor and early postpartum were analyzed. The clinical characteristics and FGM-based parameters of participants in the two groups were compared.Results: A total of 124 participants (mean age: 29.5 ± 3.5 years, 92 [74.2%] primipara) were included in the final analysis. A total of 17,571 glucose readings were retrieved. There were no significant differences in clinical characteristics between the GDM (n = 60) and NDP (n = 64) groups. The average glucose level was 92.2 mg/dL, and the level was higher in the GDM group (95.5 ± 12.1 mg/dLvs. 89.1 ± 13.4 mg/dL,P = 0.008) during the intrapartum and early postpartum periods. The data were split into the intrapartum period (from the start of labor to delivery of the placenta) and the early postpartum period (within 24 h after placental delivery) for analysis. During intrapartum, women with GDM exhibited glycemic profiles and fluctuations similar to those in the NDP group. However, women with GDM had higher postpartum glucose levels (97.7 ± 13.4 mg/dLvs. 90.8 ± 15.3 mg/dL,P = 0.009), a longer time spent >140 mg/dL (8.7 ± 9.3%vs. 5.9 ± 10.3%,P = 0.011), and greater glycemic fluctuations than those with NDP. Postpartum hyperglycemia in GDM might be associated with high parity and postprandial glucose abnormalities in GDM screening tests.Conclusion: Compared to those with normoglycemia, pregnant women with GDM receiving lifestyle interventions alone had similar intrapartum glucose profiles but higher early postpartum glucose levels and greater glucose variability, providing evidence for modification of the current perinatal glucose monitoring strategy for GDM.Trial Registration: ChiCTR.org.cn, ChiCTR2000030972.展开更多
Dear Editor,The severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)was identified as the cause of an outbreak of a global pandemic of coronavirus disease 2019(COVID-19)in December 2019.1 COVID-19 often starts ...Dear Editor,The severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)was identified as the cause of an outbreak of a global pandemic of coronavirus disease 2019(COVID-19)in December 2019.1 COVID-19 often starts with nonspecific upper respiratory tract symptoms,making it difficult to distinguish from other diseases that present similar symptoms,such as fever,lung infection,and asthenia.展开更多
基金“The Strategic Cooperation Technology Projects of CNPC and CUP(Grant Number ZLZX2020-03)”“China Postdoctoral Science Foundation(Grant Number 2021M700172)”.
文摘Borehole nuclear magnetic resonance(NMR)is a powerful technology to characterize the petrophysical properties of underground reservoirs in the petroleum industry.The rising complexity of oil and gas exploration and development objectives,as well as the novel application contexts of underground reservoirs,have led to increasingly demanding requirements on borehole NMR technology including instrument design and related processing methods.This mini review summarizes the advances and applications of borehole NMR instruments along with some future possibilities.It may be helpful for researchers and engineers in the petroleum industry to understand the development status and future trends of borehole NMR technology.
基金supported by“National Natural Science Foundation of China(Grant No.42204106)”。
文摘It is of great significance to study how temperature affects the restricted diffusion in pores for an accurate evaluation of reservoir physical properties by using nuclear magnetic resonance(NMR)diffusion-transverse relaxation(D-T2)spectrum under reservoir temperature conditions.In this paper,we simulate the restricted diffusion and twodimensional(2D)NMR D-T2 spectra of water molecules at different temperatures using random-walk method.The one-dimensional(1D)restricted diffusion simulation results show that the diffusion coefficient in the pore at room temperature decays with the diffusion time and eventually reaches a plateau.Under the condition of long-time diffusion,the ratio of restricted diffusion coefficient to bulk diffusion coefficient at different temperatures tends to be the same constant.With the increase in temperature,the simulated D-T2 spectra also gradually move upward.The simulated D-T2 spectra at all temperatures are consistent with the Pade interpolation equation.In addition,the results calculated by Pade interpolation equation demonstrate that the degree of temperature influence on the D-T2 spectrum of rock is quantitatively related to the pore radius,porosity and cementation index.
基金This paper is supported by“National Natural Science Foundation of China(Grant No.42204106)”.
文摘The measurement of nuclear magnetic resonance(NMR)porosity is affected by temperature.Without considering the impact of NMR logging tools,this phenomenon is mainly caused by variations in magnetization intensity of the measured system due to temperature fluctuations and difference between the temperature of the porous medium and calibration sample.In this study,the effect of temperature was explained based on the thermodynamic theory,and the rules of NMR porosity responses to temperature changes were identified through core physics experiments.In addition,a method for correcting the influence of temperature on NMR porosity measurement was proposed,and the possible factors that may affect its application were also discussed.
基金the National Key R&D Program of China(grant No.2021YFC2500501)the Strategic Priority Research Program of Chinese Academy of Sciences(grant no.XDB38010100)+4 种基金the National Natural Science Foundation of China(grant no.82030022 and 82330020)Program for Innovative Research Team of The First Affiliated Hospital of USTC(grant no.CXGG02)the Program of Introducing Talents of Discipline to Universities,111 Plan(grant no.D18005)Guangdong Provincial Clinical Research Center for Kidney Disease(2020B1111170013)Key Technologies R&D Program of Guangdong Province(grant no.2023B1111030004).
文摘Early insulin therapy is capable to achieve glycemic control and restoreβ-cell function in newly diagnosed type 2 diabetes(T2D),but its effect on cardiovascular outcomes in these patients remains unclear.In this nationwide real-world study,we analyzed electronic health record data from 19 medical centers across China between 1 January 2000,and 26 May 2022.We included 5424 eligible patients(mean age 56 years,2176 women/3248 men)who were diagnosed T2D within six months and did not have prior cardiovascular disease.Multivariable Cox regression models were used to estimate the associations of early insulin therapy(defined as the first-line therapy for at least two weeks in newly diagnosed T2D patients)with the incidence of major cardiovascular events including coronary heart disease(CHD),stroke,and hospitalization for heart failure(HF).During 17,158 persons years of observation,we documented 834 incident CHD cases,719 stroke cases,and 230 hospitalized cases for HF.Newly diagnosed T2D patients who received early insulin therapy,compared with those who did not receive such treatment,had 31%lower risk of incident stroke,and 28%lower risk of hospitalization for HF.No significant difference in the risk of CHD was observed.We found similar results when repeating the aforesaid analysis in a propensity-score matched population of 4578 patients and with inverse probability of treatment weighting models.These findings suggest that early insulin therapy in newly diagnosed T2D may have cardiovascular benefits by reducing the risk of incident stroke and hospitalization for HF.
基金This study is funded by the Fundamental Research Funds for the Central Universities(Grant Nos.YD9110004001 and,YD9110002002,and YD9110002008)Hefei Municipal Development and Reform Commission Emergency Funding for COVID-19 disease(Grant No.BJ9100000005)+4 种基金This study was also supported by grants from National Natural Science Foundation of China(Grant Nos.81941022,82070464)Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDB38010100)This work was also supported by Program for Innovative Research Team of The First Affiliated Hospital of USTC(CXGG02)Anhui Provincial Key Research and Development Program(Grant No.202104j07020051)Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program(Grant No.2017BT01S131).
文摘Coronavirus disease 2019(COVID-19)is regarded as an endothelial disease(endothelialitis)with its patho-mechanism being incompletely understood.Emerging evidence has demonstrated that endothelial dysfunction precipitates COVID-19 and its accompanying multi-organ injuries.Thus,pharmacotherapies targeting endothelial dysfunction have potential to ameliorate COVID-19 and its cardiovascular complications.The objective of the present study is to evaluate whether kruppel-like factor 2(KLF2),a master regulator of vascular homeostasis,represents a therapeutic target for C0VID-19-induced endothelial dysfunction.Here,we demonstrate that the expression of KLF2 was reduced and monocyte adhesion was increased in endothelial cells treated with COVID-19 patient serum due to elevated levels of pro-adhesive molecules,ICAM1 and VCAM1.IL-1β and TNF-α;two cytokines elevated in cytokine release syndrome in COVID-19 patients,decreased KLF2 gene expression.Pharmacologic(atorvastatin and tannic acid)and genetic(adenoviral overexpression)approaches to augment KLF2 levels attenuated COVID-19-serum-induced increase in endothelial inflammation and monocyte adhesion.Next-generation RNA-sequencing data showed that atorvastatin treatment leads to a cardiovascular protective transcriptome associated with improved endothelial function(vasodilation,antiinflammation,antioxidant status,anti-thrombosis/-coagulation,anti-fibrosis,and reduced angiogenesis).Finally,knockdown of KLF2 partially reversed the ameliorative effect of atorvastatin on COVID-19-serum-induced endothelial inflammation and monocyte adhesion.Collectively,the present study implicates loss of KLF2 as an important molecular event in the development of COVID-19-induced vascular disease and suggests that efforts to augment KLF2 levels may be therapeutically beneficial.
基金the Fundamental Research Funds for the Central Universities (YD9110004001 to JW, YD9110002002 to XY)Emergency Research Project of Novel Coronavirus Infection of Anhui Province (202004a07020002 to ZRL202004a07020004 to ZRL)。
文摘Dear Editor,In January 2020,a widespread outbreak of coronavirus disease 2019(COVID-19)occurred after the beginning of the largest annual migration in China,which is known as the Spring Festival migration.Starting in January 20,2020,the Chinese government took a series of unprecedented measures to contain the spread of COVID-19.Because of the role of Wuhan as a central transportation hub.
基金supported by grants from the National Natural Science Foundation of China (No. 81530025) and the National Key R&D Program of China (No. 2017YFC1309600) . The work was also supported by the Fundamental Research Funds for the Central Universities (No. WK9110000137) . The funders had no role in the design and conduct of the study, the collection, analysis, and interpretation of the data, or the preparation, review, or approval of the manuscript.
文摘Background: Data on the glycemic profile of pregnant women with gestational diabetes mellitus (GDM) during the perinatal period are sparse. This study described the intrapartum and early postpartum glucose profiles among pregnant women with GDM, and analyzed factors potentially affecting glycemic parameters during the period.Methods: This was a prospective observational study conducted from March 2020 to November 2021. Pregnant women with GDM receiving lifestyle interventions alone during pregnancy and matched women with non-diabetic pregnancies (NDPs) were enrolled from among patients admitted to the obstetrics department for childbirth. Glucose monitoring was performed via a flash glucose monitoring (FGM) system on admission, and glucose readings during labor and early postpartum were analyzed. The clinical characteristics and FGM-based parameters of participants in the two groups were compared.Results: A total of 124 participants (mean age: 29.5 ± 3.5 years, 92 [74.2%] primipara) were included in the final analysis. A total of 17,571 glucose readings were retrieved. There were no significant differences in clinical characteristics between the GDM (n = 60) and NDP (n = 64) groups. The average glucose level was 92.2 mg/dL, and the level was higher in the GDM group (95.5 ± 12.1 mg/dLvs. 89.1 ± 13.4 mg/dL,P = 0.008) during the intrapartum and early postpartum periods. The data were split into the intrapartum period (from the start of labor to delivery of the placenta) and the early postpartum period (within 24 h after placental delivery) for analysis. During intrapartum, women with GDM exhibited glycemic profiles and fluctuations similar to those in the NDP group. However, women with GDM had higher postpartum glucose levels (97.7 ± 13.4 mg/dLvs. 90.8 ± 15.3 mg/dL,P = 0.009), a longer time spent >140 mg/dL (8.7 ± 9.3%vs. 5.9 ± 10.3%,P = 0.011), and greater glycemic fluctuations than those with NDP. Postpartum hyperglycemia in GDM might be associated with high parity and postprandial glucose abnormalities in GDM screening tests.Conclusion: Compared to those with normoglycemia, pregnant women with GDM receiving lifestyle interventions alone had similar intrapartum glucose profiles but higher early postpartum glucose levels and greater glucose variability, providing evidence for modification of the current perinatal glucose monitoring strategy for GDM.Trial Registration: ChiCTR.org.cn, ChiCTR2000030972.
基金This study is part of the project of“Construction of a bio-information platform for novel coronavirus pneumonia(COVID-19)patients follow-up in Anhui”(ChiCTR2000030331)This study was approved by the institutional board of the First Affiliated Hospital of University of Science and Technology of China(2020-XG(H)-009)+3 种基金This work was supported from the National Key R&D Program of China(Grant No.2018YFA0508000)(SZ)Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB29030101)(SZ)the National Natural Science Foundation of China(Grants No.81822021,91842105,31770990,81821001)(SZ)the Fundamental Research Funds for the Central Universities(Grant No.WK2070000159)(SZ).
文摘Dear Editor,The severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)was identified as the cause of an outbreak of a global pandemic of coronavirus disease 2019(COVID-19)in December 2019.1 COVID-19 often starts with nonspecific upper respiratory tract symptoms,making it difficult to distinguish from other diseases that present similar symptoms,such as fever,lung infection,and asthenia.